The present invention relates to a tire valve, in particular gas and/or air tire valve, according to the preamble of the main claim, and a moulded seal which is suitable and provided in particular for use in such a valve.
Various approaches are known from the state of the art for sealing against air loss between an air tire valve and the valve bore (below also: rim bore) surrounding the air tire valve in the air tire rim. Firstly, so-called shoulder or flat seals exist, secondly O-ring seals are used.
However, both solutions, considered in each case in themselves, are disadvantageous technically: A shoulder or flat seal typically consisting of a flat rubber ring and optionally provided with a shoulder section, places relatively small demands on the evenness of the support surface (that is, the outer-lying flat edge section of the rim bore) and on the aperture tolerances of this rim bore, since the large rubber volume of such seals compensates deviations in simple manner. However, it is disadvantageous that during installation of valves using such seals, (low) torque limits may not be exceeded, this would lead to the destruction of the seal. Since in addition the sealing elements are deformed under pressure, very low release moments for the union nut securing the valve are usually produced in disadvantageous manner.
On the other hand, the known O-ring seals facilitate very much higher tightening moments, since the union nut engages directly on the edge section of the rim bore and in this respect a metal-metal contact exists; correspondingly high release moments can advantageously be achieved for the securing union nut. On the other hand, it is disadvantageous that such an O-ring seal places very high requirements on the evenness of the support surface in the rim bore edge region and the bore tolerances themselves, so that here in some cases considerable additional expense is necessary for manufacture and assembly. The object of the present invention is therefore to provide an improved air seal between a tire valve and the tire rim surrounding it, wherein this seal should place firstly, fewer requirements on the surface condition or evenness of the rim surface in the rim bore edge region, but secondly high tightening moments should be ensured for the union nut securing the valve.